The court heard argument in a challenge from Australian investors who want to sue the Melbourne-based National Australia Bank for securities fraud in U.S. federal court. The investors say they should have access to American courts because the claim of fraud relies on the actions of a bank-owned mortgage servicing company in Florida.

But none of the justices appeared to accept the investors' argument.

"Australian plaintiffs, Australian defendants, shares purchased in Australia. It has Australia written all over it," Justice Ruth Bader Ginsburg said. "Isn't the most appropriate choice the law of Australia rather than the law of United States?"

The court could use the case to clarify whether and when disputes over international dealings can be resolved in American courts, which often are more generous to plaintiffs than foreign courts.

Business interests and the governments of Australia, France and Great Britain are urging the court rule in favor of the bank.

San Francisco police thought the same with a father and son team they suspected of abusing the state's medical marijuana law by allegedly operating an illegal trafficking operation.

But both cases were tossed out along with many other marijuana possession cases in recent weeks because of a California Supreme Court ruling that has police, prosecutors and defense attorneys scrambling to make sense of a gray legal area: What is the maximum amount of cannabis a medical marijuana patient can possess?

No one can say for sure how many dismissals and acquittals have been prompted by the ruling, but the numbers are stacking up since the Supreme Court on Jan. 21 tossed out Patrick Kelly's marijuana possession conviction.

The high court struck down a 7-year-old state law that imposed an 8-ounce limit on the amount of pot medical users of marijuana could possess. The court said patients are entitled to a "reasonable" amount of the drug to treat their ailments.

Law enforcement officials say the ruling has made the murky legal landscape of marijuana policy in California even more challenging to enforce.

Since California voters legalized medical marijuana in 1996, there has been tension between local law enforcement officials and federal authorities, who view marijuana as absolutely illegal.

That tension is expected to become even more pronounced if the state's voters approve a November ballot measure legalizing possession of small amounts of marijuana.

The high court on Monday refused to lift a temporary injunction against Frequent Flyer Depot, Inc. A lower court judge had banned the company from working with American Airlines AAdvantage points while the airline's lawsuit against the brokers was going through the court.

American Airlines says Frequent Flyer Depot's practice of getting American's passengers to sell them their frequent flyer points is illegal. The brokers would then use the points to buy tickets for people who did not want to deal directly with American Airlines.

American says the AAdvantage program prohibits the selling of its frequent flyer points.

The brokers say buying an airline ticket from them is cheaper than buying it from American. They also say that the AAdvantage program is not a contract under which the airline can sue.

Dick Heller, the plaintiff in the landmark Supreme Court case, had challenged the new regulations, claiming the registration procedures, a ban on most semiautomatic weapons and other limitations violated the intent of the high court's decision.

U.S. District Judge Ricardo M. Urbina sided with the city, saying the Supreme Court decision did not ban reasonable limits on gun ownership designed to promote public safety.

"While the (Supreme) Court recognized that the Second Amendment protects a natural right of an individual to keep and bear arms in the home in defense of self, family and property, it cautioned that that right is not unlimited," he wrote.

The decision by Urbina, who was appointed by former President Bill Clinton, moves the case along what is likely to be a lengthy path through the legal system.

"We fully expect to go the Court of Appeals," said Heller's lawyer Richard E. Gardiner.

The RNC plans to ask the court to overturn a ruling Friday rejecting its bid to raise unlimited donations.

A three-judge federal court panel in Washington said it lacked the authority to overturn a 2003 Supreme Court ruling upholding a ban on the raising of "soft" money — unlimited donations from corporations, unions and others — by the national parties. The ban is a cornerstone of the so-called McCain-Feingold law.

The RNC argues it should be able to raise soft money for state races and other activities it says have nothing to do with federal elections. The Federal Election Commission says the ban should stand.

About a dozen banks and financial firms must defend allegations of bid rigging, limited competition and price fixing in the municipal derivatives market, a U.S. judge ruled on Thursday.

U.S. District Judge Victor Morrero's written order said the defendants, including Wells Fargo, JPMorgan Chase, UBS AG, Morgan Stanley and others, should prepare for a pretrial conference on April 30.

The case is In Re Municipal Derivatives Antitrust Litigation, U.S. District Court for the Southern District of New York, No. 08-2516.

In 2006, the U.S. Justice Department, Internal Revenue Service and Securities and Exchange Commission launched a sweeping investigation into how the derivatives, known as guaranteed investment contracts, had been priced.

Municipal bond issuers had frequently parked their proceeds from debt sales by buying these contracts, which generate income, until they needed to spend the money.

While the investigation cooled down by early 2009, with information occasionally trickling out in the banks' and insurance companies' SEC filings, it has heated back up in the last few months. At the same time, a number of counties and cities have moved to sue the companies involved.

As lawsuits over Toyota acceleration problems multiply nationwide, more than 150 attorneys gathered Wednesday to sharpen their legal skills on the eve of a major federal court hearing on whether dozens of cases will be consolidated before a single judge.

The main topic at the conference, organized by legal publisher HarrisMartin, was today's scheduled hearing before a panel of federal judges in San Diego who will choose whether to combine more than 100 Toyota lawsuits and where to send them.

Lawyers for people suing Toyota and the company itself have suggested 19 jurisdictions, according to court documents. But the panel is not required to pick from that list.

"You have consumers that have been affected in every state," said Howard Bushman, a Miami attorney whose recent cases included a $24 million settlement for AIDS patients who paid for a drug they didn't need.

Toyota has been hit with an avalanche of lawsuits that could cost it billions of dollars after its recall of 8 million vehicles worldwide, including about 6 million in the U.S., over sudden unexpected acceleration. The National Highway Traffic Safety Administration has linked 52 deaths to the accelerator problems, which Toyota has blamed on floor mats that can snag accelerator pedals or on pedals that sometimes stick.